Question

What is exchanged between mycorrhizae and plant roots?

a) plants provide sugar in exchange for water

b) plants provide shelter in exchange for minerals and sugars

c) plants provide minerals in exchange for organic compounds

d) plants provide organic compounds in exchange for minerals

Answer 1

Option d is the correct answer. Mycorrhizae is a mutualistic association between a fungus and roots of vascular plants. Plants produce organic compounds (sugars-carbohydrate) from inorganic compounds in the presence of sunlight with the help of chlotophyll by the process of photosynthesis. This organic compounds are transported to the different plant parts including roots. Fungus colonized in the roots of plants get this organic compounds for their nutrition and provide water and minerals to the plants by enhancing the absorbing surface area of the roots.

Here option a also seems to be correct but actually not, because fungus make available some specific minerals (like phosphate) to the plants which a plant cannot obtained without this mutualistic association. Thus, option d is the correct answer.